The application of the acoustic spectrophonometer to biomolecular spectrometry: a step towards acoustic ‘fingerprinting’
The application of the acoustic spectrophonometer to biomolecular spectrometry: a step towards acoustic ‘fingerprinting’
复制标题
声学分光计在生物分子光谱测定中的应用：迈向声学“指纹”的一步
DOI：
10.1002/jmr.666
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发表时间：
2004
影响因子：
2.7
通讯作者：
C. Lowe
中科院分区：
文献类型：
--
作者：
A. Stevenson;B. Araya;R. S. Sethi;H. Mehta;C. Lowe
描述了一种用于研究固-液界面上生物分子性质的可调谐声学生物传感器。在目前的格式下，该设备可以调谐到6.5千兆赫到1.1千兆赫之间的频率，以便提供独特的检测功能：传感器表面的可变逝去波厚度。其成功实施的关键是仔细选择能够在固-液界面产生剪切声波的天线设计。由于螺旋线圈的电气特性，这种非接触格式使其能够恢复100个不同的谐波频率上的共振剪切声波。为了验证这种多频传感概念，将石英盘表面暴露在免疫球蛋白G(Ig G)溶液中，形成吸附的单分子层，然后再次加入蛋白A和Ig G以形成多层膜。在6到600 MHz的频率下，每一层都产生了光谱，并显示了两个特征阶段：与传统的索布里关系式一致的低兆赫频率的初始阶段，以及可能朝向高频到千兆赫的额外阶段，我们认为这与生物分子膜的结构有关。这种两相行为从高频和低频之间的差异而不是从任何明显的频率转变中明显可见，从逝去波厚度减小到纳米尺寸以及薄膜和流体系统中已知发生的薄膜共振现象中可以预见到这种两相行为。这些测量表明，我们这里介绍的单元件声生物传感器可能形成了以类似于光学光谱学的方式产生声分子光谱或“声指纹”的基础。版权所有©2004 John Wiley&Sons，Ltd.
A tunable acoustic biosensor for investigating the properties of biomolecules at the solid–liquid interfaces is described. In its current, format the device can be tuned to frequencies between 6.5 MHz and 1.1 GHz in order to provide a unique detection feature: a variable evanescent wave thickness at the sensor surface. The key to its successful implementation required the careful selection of antennae designs that could induce shear acoustic waves at the solid–liquid interface. This non‐contact format makes it possible to recover resonant shear acoustic waves over 100 different harmonic frequencies as a result of the electrical characteristics of the spiral coil. For testing this multifrequency sensing concept the surface of a quartz disc was exposed to solutions of immunoglobulin G (IgG) to form an adsorbed monolayer, whence protein A and IgG were added again in order to form multilayers. Spectra at frequencies between 6 and 600 MHz were generated for each successive layer and revealed two characteristic phases: an initial phase at the low megahertz frequencies consistent with the conventional Sauerbrey relation, and a possible additional phase towards the high megahertz to gigahertz frequencies, that we believe relates to the structure of the biomolecular film. This two‐phase behaviour evident from differences between high and low frequencies, rather than from any distinct frequency transition, was anticipated from the reduction in evanescent wave thickness down to nanometre dimensions, and thin film resonance phenomena that are known to occur for film and fluid systems. These measurements suggested that the single element acoustic biosensor we present here may form the basis from which to generate acoustic molecular spectra, or ‘acoustic fingerprints’, in a manner akin to optical spectroscopy. Copyright © 2004 John Wiley & Sons, Ltd.